The present invention relates to a method and an apparatus for adjusting the static angular position of a floating-type magnetic head unit.
It is an essential requirement of a floating-type magnetic head unit to hold at a higher accuracy the static angular position of a magnetic head supported with a head support for achieving a high density recording and reproducing. The static angular position of the magnetic head includes a pitch angle and a roll angle.
In common, the magnetic head in the magnet head unit is bonded by adhesive to one end of the head support (a suspension) and its static angular position may be displaced from a desired angle.
The magnetic head is an expensive component manufactured through elaborate processes and mounted on the head support at a high accuracy in the magnetic head unit. Even if its static angular position is inadequate in the magnetic head unit, the magnetic head shall hardly be discarded as a defective component.
A means for adjusting an error of the static angular position has hence been developed where a mechanical pressure is applied with the use of a pressing jig. Such a static angular position adjusting method using the pressing jig includes the steps of applying the pressure onto one point along the axis on a load beam with the other point acting as a fulcrum thus to bend the load beam or adjust the static angular position of the magnetic head.
However, when the load beam is bent by the mechanical pressure, it may easily be sprung back by its restoring effect. Accordingly, the load beam has to be bent to a degree greater than the desired deflection for the static angular position.
As the load beam is bent largely, a gap may be created between a flexible member and a projection (dimple) through which a load is applied from the load beam to the flexible member, hence resulting in the generation of so-called dimple floating. The dimple floating inhibits the load beam from applying a load onto the flexible member, thus declining the floating characteristic of the magnetic head.
Alternatively, the flexible member joined to the free end of the load beam may be bent for adjusting the static angular position. In this case, the drawback attributed to the bend of the load beam will remain.
Most of the magnetic head units used in magnetic disk drives for improving the impact resistance are equipped with a limiter mounted on the flexible member to limit the movement range of a slider. The magnetic head unit of such a type becomes small in the permissive range of displacement of the flexible member due to the limiter. As a result, the displacement may hardly be adjusted to a desired degree for determining the static angular position.